WordNet sense 1 (an enzyme that catalyzes the conversion of superoxide into hydrogen peroxide and oxygen):

superoxide dismutase

WordNet sense 2 (someone who engages in anal copulation (especially a male who engages in anal copulation with another male)):

bugger, sodomite, sodomist

WordNet sense 3 (surface layer of ground containing a mat of grass and grass roots):

greensward, sward, turf